EDITION #6: Tomatoes Processing & Fresh Market

Transcription

1 University of California Cooperative Extension Vegetable Notes Fresno, Tulare and Kings Counties EDITION #6: Tomatoes Processing & Fresh Market December 2004 IN THIS ISSUE Vegetable Production Meeting JAN 21 Process Tomato Variety Trial Results Direct Seed vs Transplants Transplant Density Study MANAGING TOMATO SOLUBLE SOLIDS with Drip Irrigation Results from 7 Field Trials in Fresno & Kings Counties Evaluating EFS Varieties Dodder Management in Tomatoes Variety Tolerance to Sandea Fresh Market Tomato Variety Trials - FIELD & POSTHARVEST Summary SOURCES OF INFORMATION Vegetable Crop Farm Advisors - SJV FRESNO Shannon Mueller (559) KERN Joe Nuñez (661) MERCED & MADERA Scott Stoddard (209) SAN JOAQUIN Bob Mullen, Emeritus (209) STANISLAUS Jan Mickler (209) TULARE & KINGS Michelle Le Strange (559) , Ext. 220 Newsletter Editor Michelle Le Strange 4437-B S. Laspina Street Tulare, CA mlestrange@ucdavis.edu Vegetable Production Meeting South San Joaquin Valley UC West Side Research & Extension Center, Five Points FRIDAY Morning - January 21, :00 Registration Coffee and refreshments 8:30 Welcome Michelle Le Strange and Shannon Mueller 20 minute presentations by all speakers Weed Control Update in Onions and Garlic Kurt Hembree, Farm Advisor, Fresno Co. White Rot Update in Garlic Shannon Mueller, Farm Advisor, Fresno Co. Symptoms and Management of Tomato Spotted Wilt Virus Scott Stoddard, Farm Advisor, Merced & Madera Counties Powdery Mildew Control Evaluations in Tomatoes and Melons Jan Mickler, Farm Advisor, Stanislaus County Food Safety Concerns in Vegetable Production & Handling Trevor Suslow, Postharvest Specialist, UC Davis 10:20 Refreshment Break Comparison of Direct Seed vs Transplant Crop Establishment and Population Influence on Processing Tomatoes Gene Miyao, Farm Advisor, Yolo, Solano, & Sacramento Co. Transplant Spacing with Multiple Plant Densities for Curly Top? and Evaluating Extended Field Storage (EFS) Varieties Michelle Le Strange, Farm Advisor, Tulare & Kings Co. Fertigation of Drip-Irrigated Row Crops Blaine Hanson, Irrigation Specialist,UC Davis Deficit Irrigation & K Fertigation to Improve Tomato Fruit Quality Paul Johnstone, Post Graduate Researcher, UC Davis Postharvest Evaluations of SmartFresh (1-MCP) for Fruit & Leafy Vegetables - Marita Cantwell, Postharvest Specialist, UC Davis 12:20 pm Adjourn 2 hours DPR and CCA credit requested This meeting is open to any interested party. Meeting facility is handicap accessible. For more information call: Michelle Le Strange (559) or Shannon Mueller (559) or Chris Robles at UC WSREC (559)

2 Statewide Processing Tomato Variety Trials Fresno County Results Michelle Le Strange, Farm Advisor, Tulare and Kings Counties Four early and 6 mid-season variety tests were conducted throughout the major processing tomato production regions of California during the 2004 season. The major objective is to conduct processing tomato variety field tests that evaluate fruit yield, Brix (a measure of soluble solids %), color, and ph in various statewide locations. The data from all test locations are used to analyze variety adaptability under a wide range of growing conditions. All major areas of production had at least one test to identify tomato cultivars appropriate for that specific region. As in the past, both replicated and observational lines were evaluated. These tests are designed and conducted with input from seed companies, processors, and other allied industry and are intended to generate information useful for making intelligent management decisions. Procedures Early maturity tests were planted in February or early March and mid-season lines were planted from March to May. New varieties are typically screened one or more years in non-replicated observational trials before being included in replicated trials.tests were primarily conducted in commercial production fields with grower cooperators, however the Fresno trials were located at the UC West Side Research and Extension Center [WSREC] near Five Points. Each variety was usually planted in one-bed wide by 100 foot long plots (Fresno used 75 foot long plots). Plot design was randomized complete block with four replications for the replicated trial. The observational trial consisted of one non-replicated plot directly adjacent to the replicated trial. Seeding or transplanting was organized by the Farm Advisor at approximately the same time that the rest of the field was planted. All cultural operations, with the exception of planting and harvest, were done by the grower cooperator using the same equipment and techniques as the rest of the field. All test locations were primarily furrow irrigated. A field day or arrangements for interested persons to view the plots occurred at all of the tests. Results A complete research report can be found at the VRIC website Click on Vegetable Information, Choose Tomato as the crop, scroll down to other and click on 2004 Statewide Processing Tomato Variety Evaluation trials. OR call a Farm advisor and ask them to mail you a copy. Results from the Fresno trials are below. EARLY REPLICATED PROCESSING TOMATO VARIETY TRIAL Fresno County 2004 Seeded FEB 13 Harvested JULY 13 Yield Brix Brix VARIETY T/A % Yield Color ph H A (01) 22.0 (04) 4.45 H AB (02) 21.3 (01) 4.47 Calista 32.1 BC (04) 22.0 (04) 4.50 U BC (07) 24.8 (11) 4.44 Hypeel BC (03) 23.0 (06) 4.35 PX BCD (05) 23.0 (06) 4.41 UG C D (06) 23.3 (10) 4.43 H C D (09) 23.0 (06) 4.43 Sun D (10) 23.0 (06) 4.44 APT D (08) 21.8 (02) 4.42 HA D (11) 21.8 (02) 4.55 Average C.V.% MID SEASON REPLICATED PROCESSING TOMATO VARIETY TRIAL Fresno County 2004 Seeded MAR 19 Harvested AUG 13 Yield Brix VARIETY T/A % Brix Yield Color U A (01) 26.5 (18) 4.35 (11) H AB (02) 25.8 (13) 4.23 (01) H 5503 EFS 48.4 ABC (04) 25.0 (06) 4.32 (08) Sun ABC (05) 25.0 (06) 4.36 (15) H BCD (03) 25.0 (06) 4.30 (06) H C D E (07) 24.0 (01) 4.33 (10) H 5803 EFS 41.4 DEF (06) 24.8 (05) 4.30 (05) Red Sky 41.2 DEF (08) 25.3 (10) 4.35 (13) UG DEF (10) 24.3 (02) 4.36 (16) H EFG (12) 24.5 (03) 4.27 (04) H EFG (13) 25.8 (13) 4.40 (18) CPL 4863-N 37.5 EFG (16) 25.0 (06) 4.35 (12) PS EFG (09) 25.8 (13) 4.25 (02) Halley FG (11) 24.5 (03) 4.26 (03) Sun FG (15) 25.8 (13) 4.33 (09) U FG (18) 25.5 (11) 4.32 (07) PX FG (14) 25.5 (11) 4.37 (17) La Rossa 34.2 G (17) 26.3 (17) 4.36 (14) ph Average N.S C.V. %

3 Direct Seed vs. Transplant Evaluation in Processing Tomatoes Gene Miyao, Farm Advisor, Yolo, Solano & Sacramento Counties More Field Trials: Testing continued in 2004 on comparing transplants with direct seed in a field trial northwest of Woodland with Joe Muller and Sons. We direct seeded into single lines on March 23 when the grower seeded. Three weeks later we returned to mechanically transplant when our field seedlings were at the two-true leaf stage. Sprinkler irrigation established the crop, though residual soil moisture was good. Conditions were very good for crop establishment for both the direct seed and transplants. Halley was our primary variety. We thinned the direct seed into clumps of 3 plants centered on 12, 16, 20 or 24 inches and transplanted with plugs with single plants at 12, 16, 20 and 24 inches. Varieties AB 2 and HM 830 were also planted but only on 12-inch spaced clumps for direct seed and 16-inch spacing for the transplants. We presumed those configurations would represent the norm for direct seed as well as for transplants. Full stands were maintained at the early stages by replanting with transplants during the first few weeks. Few replacements were needed. Furrow irrigation was used for the bulk of the remaining season. There was minor damage from Phytophthora root rot in this Rincon silty clay loam, class 2 soil. Verticillium wilt was prevalent and caused moderate loss of canopy during the later growth stage. Harvest was timely with both establishment methods nearing optimal maturity together. Results: Yield between direct seed and transplants were similar, although this time transplants had the advantage, 39 vs 41 tons, respectively (Table). Direct seeded Halley compensated well across our spatial differences. As a transplant, Halley was less forgiving. Yields were slightly reduced linearly as spacing between plants increased. Transplant yields ranged from 38 to 41 T/A. However, the transplant Halley spacing of 16 inches apart was similar to the 12-inch spacing, 40.0 vs 41.0 tons, respectively. Both AB 2 and HM 830 yields responded similarly to Halley between transplanting and direct seeding. AB 2 was the highest yielding variety with 45 plus T/A. Transplants had fewer sunburn damaged fruit, fewer blossom end rot and more pink fruit. Brix levels were high, averaging 6.0, for both direct seed and transplants in this test. Bottom line: Yield and performance of transplants were very similar to direct seed. Discussion: At this point I am unsure of the value of continued comparisons. It seems that further evaluations would likely produce results where some locations and conditions would slightly favor one planting method, but without a consistently superior method identified. The upshot appears to be that establishment method is comparable between the two. Marketable Spacing Yield % % % sun % lbs per VARIETY Method (inches) tons/acre pink green burn BER 50 Fruit 1 Halley seed Halley seed Halley seed Halley seed Halley transplant Halley transplant Halley transplant Halley transplant AB 2 seed AB 2 transplant HM 830 seed HM 830 transplant LSD 5% NS 6.4 NS NS C.V seeded Linear NS NS NS NS NS NS Quadratic NS NS NS NS NS NS transplanted Linear * * 0.1 NS NS NS Quadratic NS NS NS NS NS NS direct seed transplant ** *** 0.11 *** * NS NS Not Significant at probability 0.05, *significant at probability of 0.05, ** significant at probability of

4 Transplant Density in the Control of Curly Top Virus Michelle Le Strange, Farm Advisor, Tulare & Kings Counties Overview: When curly top virus occurs on the west side of the San Joaquin Valley the amount of damage to tomatoes appears to be more extensive in transplant fields compared to direct seeded fields. Growers have been switching to transplants for a number of reasons and in the process the total number of plants per acre has been reduced. Fewer plants per area may create conditions favorable for the beet leafhopper, Circulifer tenellus, the vector of the virus, since it is believed that dense stands of tomatoes discourages visitation by leafhoppers. A field trial was initiated to investigate in-row spacing (15 vs. 30 inches), number of plants per transplant plug (1, 2, or 3), on a medium vine size variety (Halley 3155) and a large vine size variety (AB2) in efforts to minimize effect of curly top virus in processing tomatoes. Disease incidence in this trial was too low to affect the results. Yield results indicate that these two varieties responded similarly to increasing plant density. In general a 15-inch spacing with 2 or 3 plants per plug yielded significantly more than 1 plant per plug regardless of variety. A 30-inch plant spacing with only 1 plant per plug yielded the least. Procedures: A transplant density experiment was established on May 21, 2004 in a commercial field of processing tomatoes grown in the Five Points - Huron area in the San Joaquin Valley. Though early incidence of curly top virus appeared low throughout the Westside of the SJV, the trial was initiated to determine yield differences of plantings of various densities. Two varieties Halley 3155 (medium vine size) and AB2 (large vine size) were seeded at 1, 2, and 3 seeds per transplant plug and grown in a commercial greenhouse until they were hand transplanted in the field at a 15 and 30 spacing. Individual plot size was one 60-inch bed wide x 100 row length. The field was grown under sprinkler and furrow irrigation and was machine harvested on October 7, Fruit samples from the mechanical harvester were hand-sorted for defects. The incidence of curly top virus was too low in the field to have an effect on yield. Results are a reflection of plant density and variety differences. Results: In general yields were low for Fresno County, perhaps reflecting the late planting and fruit set problems associated with heat. Yields ranged from 30.7 to 17.4 tons per acre. Variety, in-row spacing, and the number of plants per transplant plug each had an effect on yield (Table 1 and Figure 1). Variety: Over all density treatments Halley 3155 (a medium size vine) averaged 2.3 more tons per acre than AB2 (a large size vine). This proved statistically significant, although the tonnage difference between varieties at the density treatments was small. At a 15 plant spacing across all plug densities Halley averaged 28.3 and AB2 averaged 26.6 tons per acre. At a 30 plant spacing across all plug densities Halley averaged 24.7 and AB2 averaged 21.7 tons/acre. Halley also yielded higher than AB2 at the different plug densities and across the in-row plant spacing as shown in the tables and charts. Tons/Acre Halley AB2 Average 15 spacing a 30 spacing b Average LSD In-row spacing: The closer in-row spacing of 15 inches brought higher yields than a 30-inch in row spacing across plug density and within and between varieties. Number of plants per transplant plug: When both in-row spacings were averaged, 2 and 3 plants per plug brought higher yields than one plant per plug, however there was no yield advantage with three plants over two plants per plug. This held true in Halley and AB2. Tons/Acre Halley AB2 Average 1 plant/plug b 2 plants/plug a 3 plants/plug a Avg. (LSD = 1.8) 26.5 a 24.2 b 25.3 LSD In this trial a 15-inch in-row plant spacing with either 2 or 3 plants per plug yielded the most fruit. A 30-inch plant spacing with 3 plants per plug yielded about the same as a 15 inch spacing with 2 plants per plug. A 30-inch spacing with only 1 plant per plug yielded the least regardless of variety. Although the variety with medium vine size, Halley 3155, yielded more than AB2, the variety with larger vine size, yield differences were small and the varieties performed consistently across density treatments. 4

5 Table 1. Effect of variety, in-row spacing, and plant number in transplant plug on yield of processing tomatoes, Fresno In-row Plants Percent lbs per Variety Spacing in Plug Yield T/A red green sunburn rot 50 fruit Halley 15" a 75 ab 5 ab 4 d 17 abc 7.6 a Halley 15" ab 75 ab 5 ab 6 bcd 13 abcd 8.5 a AB2 15" abc 82 ab 4 ab 6 bcd 8 d 8.5 a Halley 30" abc 73 ab 3 b 8 abc 15 abcd 8.0 a AB2 15" abc 76 ab 7 ab 5 cd 13 bcd 8.5 a Halley 30" bcd 69 b 4 ab 8 abc 19 ab 7.8 a AB2 30" bcd 76 ab 5 ab 9 ab 11 bcd 7.2 a Halley 15" cd 70 b 2 b 6 bcd 22 a 7.6 a AB2 15" cde 79 ab 3 b 8 abc 10 cd 7.1 a AB2 30" de 71 b 3 b 9 ab 17 abc 7.3 a Halley 30" ef 73 ab 4 ab 7 abcd 15 abcd 7.7 a AB2 30" f 71 b 4 ab 10 a 14 abcd 7.5 a LSD ns CV % Halley average 26.5 a AB2 average 24.2 b LSD ns no significant difference Results followed by same letter are not significantly different from each other. YIELD T/A Figure 1: YIELD of Halley & AB2 at 2 in-row spacings with 1, 2 or 3 plants/plug 15" 30" 15" 30" 1 plant 2 plants 3 plants Halley AB2 Trends in Marketing Interesting Facts Roberta Cook, Agricultural Economist, UC Davis US Fresh-Cut Vegetable Facts Fresh-cut veggies represented 31% of all prepackaged produce retail sales in Carrots were about half the $1.3 billion fresh-cut veggie category, followed by spinach ($108 million), potatoes ($87 million), celery ($85 million) and mixed vegetables ($69 million) 77% of consumers purchase fresh-cut veggies, but on average, only once every 9 weeks US Sales of Salads by Type for 2002/03 in million $ Fresh-cut Salads $ volume Segment share % Total $2,357, % Blends 1,039,863 44% Garden (IBB) 702,950 30% Kits 283,653 12% Organic 144,927 6% Romaine hearts 107,278 5% Slaw 79,

6 Managing Tomato Soluble Solids with Drip Irrigation Tim Hartz, Vegetable Crops Specialist, Dept of Plant Sciences, UC Davis Paul Johnstone, Post Graduate Researcher, UC Davis, Michelle Le Strange, Farm Advisor, Tulare & Kings Counties With the explosion of drip irrigation use in processing tomato production the issue of managing fruit soluble solids has become a hot topic. We conducted a series of trials in previous years, examining the response of tomato fruit to soil moisture stress. Our most important finding was that only green fruit are affected by water stress; once a tomato ripens, its soluble solids concentration (SSC) cannot be increased by water stress. This suggests that the only way for a grower to substantially increase SSC is to begin to dry down the field while most fruit are still green Field Trials: We conducted trials in 7 drip-irrigated fields in Fresno and Kings Counties to evaluate the effects of late-season deficit irrigation on fruit yield and SSC. These fields represented different growers, a range of soil conditions, and a harvest period from July 19 to September 21; details are given in Table 1. The cooperating growers determined the timing and volume of irrigation delivered to their fields. Water meters were installed in the drip lines of 7 individual beds, ft from the tail end of the field; on 5 of these lines a gate valve was also installed. About 4-7 weeks before harvest (corresponding to 5-25% of fruit having begun external color change) the gate valves were partially closed, reducing irrigation flow in those lines by 25-50%. Fruit yield and SSC from the rows receiving reduced irrigation were compared with that of matching rows receiving the growers irrigation treatment. (In field 4 the trial was not set up until approximately 25% of the fruit were red, so the reduced irrigation treatment consisted of complete irrigation cutoff). On the day the reduced irrigation treatment began, approximately 20 fruit per row at the turning or pink stages of ripeness (as defined by USDA fresh market standards) were collected, blended, and evaluated for SSC by refractometer. A second set of later-maturing fruit were collected and analyzed 2-4 weeks later. At harvest, fruit were graded into marketable (sound red fruit), green, and cull (sunburn, limited use, and rot) categories, and marketable yield calculated. SSC, ph, and color were determined on blended samples of red fruit from each subplot. Results: Based on prior research, crop water requirement for full irrigation over the last 4-6 weeks of the season would require approximately 80-90% of CIMIS ETo. By this criterion, all growers followed a deficit irrigation regime, varying in the degree of severity (Table 2). No prolonged irrigation cutoff period was employed in any field; all growers continued to make light irrigations to within 14 days of harvest. SSC of early-maturing fruit 6 varied from 4.2 to 5.9 o brix among fields (Fig. 1). This range was partly attributable to cultivar differences, and partly to field-specific factors. For example, in field 2 the wetting pattern quickly came to the soil surface, and the grower had been deficit irrigating for several weeks before the trial began in an attempt to keep the top of the beds dry; this was reflected in the very high brix of early-maturing fruit. The pattern of subsequent SSC development was quite consistent across fields. Later-maturing fruit (those exposed to deficit irrigation while still green) showed substantially increased SSC. Overall fruit SSC at harvest was intermediate between that of early- and late-maturing fruit. These results were consistent with our prior observations that, after ripening, fruit SSC does not increase regardless of subsequent soil moisture stress. High yields were observed at all sites, with extraordinarily high yields in fields 1 and 3 (Table 2). High SSC was also achieved, across all fields averaging 5.5 o brix in the grower plots. Although the trends were not statistically significant for all individual fields, across fields the reduced irrigation treatment reduced marketable fruit yield slightly. However, the yield loss was offset by a corresponding increase in SSC; overall, brix yield was equivalent in both irrigation treatments. Across fields, differences between irrigation treatments in cull rates and blended fruit color were not significant. None of the trial fields showed severe vine decline at harvest; only in field 6 could the reduced and grower irrigation treatments be distinguished visually. These results indicated that processing tomatoes can tolerate a significant degree of water stress before brix yield is compromised. Irrigation regimes as low as 20-40% of ETo over the fruit ripening period did not significantly reduce brix yield when compared to wetter treatments. This means that growers have substantial flexibility in lateseason drip irrigation scheduling, enabling them to tailor irrigation based on field-specific factors such as the SSC of early-ripening fruit. The consistent pattern of increasing fruit SSC in response to deficit irrigation suggested that SSC monitoring of ripening fruit could be a useful tool in irrigation scheduling; the large differences among fields in SSC of early-ripening fruit emphasized that some fields may require more severe irrigation deficits to achieve acceptable fruit SSC than others. Summary: To summarize our drip irrigation scheduling work over the last 3 years, initiating deficit irrigation early in the fruit ripening period, and applying 40-60% of ETo from then until harvest, is likely to achieve acceptable fruit SSC with minimal yield reduction under most field

7 conditions. In fields in which early-ripening fruit are significantly below the desired SSC level, more severe deficit may be warranted. To date we have not conducted irrigation trials in a field with severe vine decline problems; the ability to substantially increase fruit SSC by deficit irrigation may be compromised in fields in which factors other than water stress (foliar or root pathogens, nutrient deficiency, etc.) seriously reduce late-season vine vigor. Also, initiating deficit irrigation as early as 6 weeks preharvest may increase the potential for root intrusion into the drip tape; although this has not been a wide-spread problem in these trial fields, growers should be vigilant. Table 1. Soil texture, cultivar, and harvest date for 2004 drip irrigation trial fields. Field Location Soil texture Cultivar Harvest date 1 Five Points sandy clay loam AB 2 19 July 2 Cantua Creek sandy clay loam HM July 3 Five Points sandy clay loam AB 2 23 July 4 Huron clay Halley 5 Aug 5 Firebaugh clay Peto Aug 6 Firebaugh clay Heinz Sept 7 Huron clay Heinz Sept Fruit SSC ( o brix) early-maturing fruit late-maturing fruit harvest composite Fig. 1. Fruit soluble solids concentration (SSC) development in the grower irrigation treatment over the fruit ripening period Field Table 2. Effect of late-season irrigation management on tomato yield and fruit soluble solids concentration (SSC). Irrigation Cutback initiation % of ETo applied Mkt. yield Soluble solids Brix yield Field treatment (days preharvest) in cutback period (tons/acre) ( o brix) (tons/acre) 1 grower reduced ns * ns 2 grower reduced ** ns * 3 grower reduced ns ns ns 4 grower reduced ns ns ns 5 grower reduced ns ns ns 6 grower reduced * * ns 7 grower reduced ns ns ns Ave grower reduced * ** ns ns, *, **irrigation treatments not significantly different, or significantly different at p < 0.05 or 0.01, respectively 7

8 Evaluation of EFS Varieties over Time of Harvest Michelle Le Strange, Farm Advisor, Tulare and Kings Counties Overview: Certain processing tomato varieties have been bred for Extended Field Storage (EFS). Some of these are included in the UC statewide variety trials, however under that protocol the EFS lines are only harvested one time and this procedure does not adequately address or evaluate a variety s potential for extended field storage. It is well documented that yields of processing tomatoes decrease during periods when high-sustained air temperatures occur and disrupt fruit set. Previous work by others has investigated planting EFS varieties early and letting ripe fruit store in the field for long periods before harvesting. This was not the aim of this project. The results from this one study showed that under some field conditions fruit yield (T/A) decreased fairly fast (within 7 days) for all tested varieties and quality of yield was not maintained. Some varieties performed better than others, but more field tests are needed. Procedures: A field study was established in Five Points at the UC WSREC in Fresno County on May 26, Five EFS varieties were selected to compare with a standard tomato variety, Halley Seedlings were hand transplanted on 12-inch spacing and grown with typical commercial practices under furrow irrigation. Irrigation cutoff was on August 20, Plot size was 45 of row on a 66 tomato bed. The trial was arranged in a split plot design for three separate harvest dates without disrupting the growth of tomatoes on neighboring beds. Each variety was replicated five times within each harvest date. At harvest time tomato roots were undercut by machine and a portion of the plot was hand harvested for fruit yield and quality. The three harvest dates were Sept 15 (111 days after transplanting (DAT), Sept 22 (118 DAT), and Oct 5 (131 DAT). PTAB data was collected at each harvest and samples were sent to Diane Barrett s food science lab on the UC Davis campus to gather cooked tomato data. There was virtually no insect or disease pressure in the field, however weeds were an issue. In spite of fumigation with vapam prior to planting and two herbicide applications, several hand weedings were needed to remove nightshade and patches of dodder from the field. The last weeding was timed with irrigation cutoff, which seemed to intensify vine breakdown and sunburn. Results: Harvest date affected tonnage, quality of yield, PTAB parameters, and cooked analysis of tomato fruit (data not shown). For yield and quality of yield at harvest all varieties responded similarly to delayed harvest. With each successive harvest date: Tonnage decreased Lbs/ 50 fruit decreased % green fruit decreased % rotten fruit increased % sunburned fruit increased PTAB results were less consistent and did not follow as clear a trend over harvest date. Color decreased slightly for each EFS variety, but not for Halley. Brix increased slightly for each EFS variety, but not for Halley. ph did not follow a trend. This data is from one field study and will be modified and repeated. No conclusions are being drawn at this time. Table 1. YIELD Results - EFS Varieties x Harvest Date 2004 YIELD T/A Variety AVG. H1 H2 H3 AVG. H1 H2 H3 U a 36.6 a ab 9.8 a 10.6 a 9.9 ab 9.0 a PS a 34.0 a a 9.8 a 11.0 a 9.4 ab 9.0 a U ab 37.7 a abc 9.5 a 10.4 a 9.5 ab 8.5 ab H ab 31.3 a abc 8.8 b 9.1 b 9.2 b 8.1 b Halley* 21.4 bc 31.7 a c 9.7 a 10.4 a 10.2 a 8.6 ab H c 24.4 b bc 9.8 a 10.5 a 9.8 ab 9.1 a average LSD Var ns LSD H LSD H x Var ns ns CV % * check variety H1 = Sept 15 H2 = Sept 22 H3 = Oct 5 LSD@ 0.05 ns = not significant 8 Lbs/50 Fruit

9 Table 2. QUALITY of Yield Results - EFS Varieties x Harvest Date 2004 % Green % Rot % Sunburn % Rot + Sunburn Variety H1 H2 H3 H1 H2 H3 H1 H2 H3 H1 H2 H3 U PS U H Halley* H average LSD H LSD Var LSD H x Var ns ns ns ns CV % * check variety H1 = Sept 15 H2 = Sept 22 H3 = Oct 5 LSD@ 0.05 ns = not significant Table 3. PTAB Results - EFS Varieties x Harvest Date 2004 Color Brix ph Variety H1 H2 H3 H1 H2 H3 H1 H2 H3 U PS U H Halley* H average LSD H 0.72 ns ns LSD Var ns LSD H x Var ns ns ns CV % * check variety H1 = Sept 15 H2 = Sept 22 H3 = Oct 5 LSD@ 0.05 ns = not significant Dodder Management in Tomatoes Tom Lanini, Extension Weed Ecologist, University of California, Davis As Chuck Rivara of CTRI once said, Dodder is like a car accident. It s a curiosity when you see it in someone else s field, but it s a real problem when it s in yours. Dodder: A stem parasitic weed, is often considered a disease rather than a flowering plant. Germinating dodder seeds emerge as rootless, long yellow-orange thread-like leafless stems. The thread-like seedling coils around the host stem, adheres to it by adhesive discs, penetrates its tissue and vascular system via haustoria, and exploits the host by withdrawing nutrients and water. The part of the seedling in contact with the soil dies soon after haustoria 9 formation. New shoots are continuously produced, forming new attachments to the same plant and allowing attack of neighboring plants. Thus, the vigor of the host plant is lowered and crop production is dramatically reduced. Damage: Dodder that is not controlled can reduce tomato yields by over 75% and produce thousands of seeds that can remain viable for up to 20 years. Dodder is estimated

10 to be present in about 30,000 acres of tomatoes in California, in addition to parasitizing many rotational crops including alfalfa, asparagus, carrot, onion, safflower, sugarbeet and melon. Dodder also infests many broadleaf weeds. Dodder control can be achieved by avoidance, hand removal, resistant tomato varieties, and herbicides. None of these methods work 100% of the time, but all offer some hope for managing this native, parasitic weed. Another complicating factor is that several dodder species are involved, with field dodder (Cuscuta pentagona) being the most common. Avoidance: Fluctuations in soil moisture and temperature near the soil surface may initiate germination of buried dodder seed. Temperatures during the spring and early summer months are ideal for dodder emergence. However, dodder emergence in field trials was observed to cease or dramatically decline in early to mid May, despite temperatures in the optimum range for germination and emergence. We have confirmed these observations in several tomato fields. Thus, a way to avoid major dodder infestations is to plant after mid-may. Late planting can reduce dodder infestation, but that is not always practical due to cannery delivery dates. Some growers have utilized transplants in order to plant late, but still deliver tomatoes within the delivery time frame. Dodder also has a more difficult time attaching to larger plants. Shallow cultivation: Due to the absence of roots, dodder seedlings (before attachment to the crop) are easy to control by shallow cultivation. In addition, tillage may hasten drying the soil surface, thus preventing further dodder germination and emergence. Complete dodder removal can only be achieved with the destruction of the infested crop plants. Hand removal: Removal by hand crews, of the tomatoes with dodder attached, remains a viable but expensive option, when infestations are small. When infestations are extensive, hand removal would be prohibitively expensive, not to mention the loss in the tomato stand. Hand removal is often done when dodder is first detected to prevent spread and seed production. In a trial area, farm workers were observed to remove dodder about 90% of the time. The remaining 10% was generally missed, because it was too small to be easily detected. If a hand crew can be sent back through a field about 15 to 21 days after the first hand weeding, the remaining dodder plants can be removed prior to any dodder seed production. Plants with attached dodder do not need to be removed from the field unless they have viable seed. Dodder can reattach to a new host if left in close proximity to living tomato plants, but if the plants are moved 6 or more inches from the remaining tomato plants, the dodder will not be able to reach a new host. Resistant varieties: Dodder resistant tomato varieties continue to be a viable option for preventing dodder infestation. Thus far, four Heinz varieties have been shown to be dodder resistant in field trials: H9492, H9553, H9992, and H Additionally, CDX 233, H1100, H9997, and SVR , have shown excellent dodder resistance in greenhouse studies. Some dodder is able to attach and survive on these varieties, but generally, tomato yields are not reduced and dodder seed production is very low or non-existent. Varieties to avoid if dodder is potentially a problem include AB2, ENP 113, APT 410, CDX 222, H2501, H2601, H8892, and H9665, which are all highly sensitive to dodder. Herbicides: The preemergence herbicides used in tomatoes are not effective in preventing dodder germination or attachment to tomato plants. Metam sodium controls many weeds prior to vegetable planting, but hard seeded species, such as dodder are not affected. Trifluralin controls dodder well in alfalfa, but the incorporation of the herbicide in tomatoes, allows dodder seed near the soil surface to escape control. Layby herbicides, such as Tillam or Treflan, are applied too late to control attached dodder. The nature of attachment and association between host and parasite requires a highly selective herbicide to destroy the attached dodder without crop damage. Matrix (rimsulfuron) has been shown in studies conducted by Bob Mullen in San Joaquin County, to suppress dodder, particularly when split applications are used. However, the control achieved by the best Matrix treatments was only about 50%. Even when Matrix rates were increased to 2X the current label rate, dodder still survived. By the end of the season, dodder growth in the best Matrix plots was still extensive, indicating that Matrix alone is not providing adequate control. Spread by equipment: The primary means of dodder spread from field to field is on equipment. As more custom operations are performed, the chances for dodder spread increase. To prevent the spread of dodder (and other diseases), wash equipment after leaving an infested tomato field, before entering another. If new dodder patches are detected, eradication of these patches should be done before they have a chance to produce seeds. Patches can be removed by hand removal, spraying both host and parasite, with a contact herbicide or by searing with a flame-throwing torch or hand burner. 10

11 Evaluation of variety tolerance to herbicide control of yellow nutsedge and nightshade in a processing tomato/cotton production system in salty soil. Scott Stoddard, Farm Advisor, Merced and Madera Counties Summary. Certain processing tomato varieties were found to be sensitive to the new nutsedge herbicide Sandea (halosulfuron-methyl), and phytotoxicity was exasperated when Matrix (rimsulfuron, for nightshade control) was added to the tank-mix. SUN 6119 and H 9780 had more than 50% phytotoxicity one week after spraying, however, there was no significant effect on yield. No significant phytotoxicity was seen with the other herbicide treatments. Results from 2003 show that the Sandea + Matrix combination gives excellent weed control in fields with nutsedge and nightshade weed problems. It is important for growers to know that while Sandea may cause some yellowing of the plants, this effect is temporary and should not impact yield. Methods: This trial was established in a field near Los Banos to evaluate current nightshade and nutsedge herbicides on weed efficacy and crop performance in different varieties. Five processing tomato varieties and six herbicide treatments were used. The herbicide treatments consisted of: 1. Dual Magnum (metolachlor) PPI grower applied at label rate (UTC) 2. Dual + Sandea (halosulfuron-methyl) 1 oz/a + NIS 3. Dual + Matrix (rimsulfuron) 2 oz/a + NIS 4. Dual + Sencor (metribuzin) 2/3 lb broadcast 5. Dual + Sandea 1 oz/a + Matrix 2 oz/a + NIS 6. Dual + Matrix 2 oz/a + NIS + Sencor 2/3 lb broadcast The varieties used were: 1. Halley H PS SUN 6119 (not commercial release) 5. H9780 A split-plot design was used, with herbicide as the main treatment and variety the split plot treatment. Plot was located within a commercial production field, furrow irrigated. The entire field had already received a preplant incorporated (PPI) application of Dual Magnum. Varieties were transplanted May 8, Herbicide applications were broadcast applied June 16, 2004 over-the-top when plants were at full bloom. Post application phytotoxicity ratings were based on yellowing, stunting, and leaf necrosis using a scale of 0 to 10. Soil type was a Dos Palos clay loam, moderately saline (EC of 1.7 in top 12 inches). Lab analysis results are in Table 1. Results: Phytotoxicity ratings are shown in Table 2. Averaged across varieties, Sandea + Matrix tank mix caused significantly greater phytoxicity, almost 35% seven days after application, as compared to the other treatments. Matrix + Sencor tank mix ranked second at 8% damage. A strong variety by herbicide interaction indicated that the amount of phytotoxicity caused by the herbicide treatments was different between the varieties. SUN 6119 (not a commercial release) and H 9780 were much more sensitive to Sandea and Sandea + Matrix than the other varieties. Sandea + Matrix tank-mix resulted in much more phytotoxicity than either chemical alone. SUN 6119 showed more than 60% phytotoxicity 7 days after application. HOWEVER, two weeks after herbicide application, almost no phytotoxicity symptoms could be seen. Weed control ratings were very limited until the end of the season. The preplant application of Dual Magnum kept weeds under control. Additionally, the field had been in Roundup Ready cotton the previous year, which eliminated much of the nightshade and nutsedge pressure. As a result, there was no nightshade or nutsedge growing in any of the plots. By the end of the season, however, mallow, pigweed, and Johnsongrass were present in the field. The herbicide treatments did significantly reduce the amount of weed pressure as compared to the untreated check (UTC). Variety had a significant effect on yield, soluble solids, color, and ph, but there was no significant difference from herbicide treatments (Table 2). The Sandea + Matrix treatment yielded as well as the UTC in spite of the phytotoxicity symptoms earlier in the season. Table 1. Soil analysis results Depth inches NO 3 -N ppm OlsenP ppm X-K ppm ph EC ds/m Ca meq/l Mg meq/l Na meq/l Cl meq/l

12 Table 2. Crop phytotoxicity and weed control ratings as affected by herbicide treatment, Merced Treatment Variety 1 week post 2 weeks post 19-Aug yield Phyto, % Weeds Phyto, % Weeds Weeds lbs/5 ft tons/a Color SS, % ph 1. UTC Sandea Matrix Sencor Sandea + Matrix Matrix + Sencor H PS SUN H Herb treatment LSD NS NS NS NS Variety LSD Treatment x Variety *** --- ** NS CV, % Fresh Market Tomato Variety Trials FIELD EVALUATIONS 2004 Michelle Le Strange, Scott Stoddard, Bob Mullen, and Jan Mickler, Farm Advisors Introduction: Fresh market tomato variety trials are conducted in major tomato-growing regions in California to evaluate the performance of new varieties and breeding lines from commercial plant breeder programs and universities. It is important to test the varieties in several areas to assess performance under different climatic conditions and soils. The objective is to identify dependable, higher yielding and higher quality variety releases that can be grown over a wide geographic area under varying environmental conditions. To determine which varieties/lines are tested, growers/packers/shippers and seed company representatives are surveyed throughout the state. Replicated varieties have been previously tested in grower fields in California. Observed lines usually represent the plant breeder s most promising lines for California s commercial growing conditions and markets. Trial Locations: County farm advisors conduct the statewide variety trials in a uniform fashion so that local results can be compared with other locations. Three round variety trials and two roma variety trials were grown and harvested in commercial fields in Fresno County: April 16 - July 17 (92 days) UC WSREC round and roma trial -- Michelle Le Strange, Farm Advisor Merced County: May 15 July 23 (79 days) with Live Oak Farms in Le Grand -- Scott Stoddard, Farm Advisor San Joaquin County: June 9 - Sept 1 (82 days) with Tom Guido and Triple E Produce, east of Stockton, round and roma trials -- Bob Mullen and Jan Mickler, Farm Advisors The three round tomato variety trials had 5 replicated and 8 observed (non-replicated) varieties in common. Two locations had 3 more replicated and 5 more observed varieties/lines in common. Postharvest samples from all replicated varieties were collected from the Fresno and San Joaquin trials at time of harvest and transported to the Mann Laboratory at UC Davis for color, firmness, and composition evaluations at the table-ripe stage. Fruit were harvested as mature greens, but some cultivars were also harvested as vine ripe. Postharvest results follow this article. A summary of results is presented. A complete summary of all results is available from the participating farm advisors. 12

13 2004 YIELDS AND GRADES OF FRESH MARKET TOMATO VARIETIES South San Joaquin Valley - UC WSREC, Fresno County Nonmarket Market Yield TOTAL.. Yield/Acre 1*.. % Market Yield 2 Small 3 Culls 4 Yield 5 % # Variety Tons Boxes X-L Large Med T/A T/A T/A Reds 6 3 SVR a BHN ab QualitT ab QualiT ab Catalyst ab Bobcat ab L ab Shady Lady b Average LSD ns 8.1 CV % Market Yield BOXES/A QualiT 21 Figure 1 Fresh Market Tomato Combined Averages Fresno, Merced, & San Joaquin Counties SVR 2935 Bobcat Catalyst BHN 580 QualiT 23 Replicated Varieties Shady Lady L-312 Med L XL Fresh Market Tomato - POSTHARVEST EVALUATIONS Marita Cantwell, Postharvest Specialist, Dept of Plant Sciences, UC Davis In 2004, we evaluated round fresh market tomato varieties from the replicated trials in Fresno and San Joaquin Counties for color, firmness and composition at the tableripe stage. Fruit were harvested as mature-greens (MG) and vine-ripes (VR, 30-40% color). Observation varieties from Fresno County were also evaluated (data not shown). Roma varieties were also harvested from both Fresno and San Joaquin County trials at MG and VR stages. Quality measurements on fruit at the table-ripe stage are described in Table 1. Fruit were sorted and washed with chlorinated water. A minimum of 45 fruit (3 reps of 15 each) were ripened under standard conditions: 3-4 days 100 ppm ethylene at 20 C (68 F) and high relative humidity followed by placement on trays (overwrapped with food wrap to reduce but not eliminate water loss) to complete ripening at 20 C. Fruit that did not show color change within 3-4 days of ethylene treatment were discarded. VR fruit were placed on trays to complete ripening at 20 C (68 F). Fruit were evaluated when they reached the tableripe stage (color stage 6 on USDA scale days). Results for round tomato varieties are shown in Table 2. The 2004 round variety fruit generally had lower soluble solids (4.2% average for all varieties and both trials) than 2003 fruit (4.9% average), whereas % titratable acidity values were in the usual range of %. VR harvested fruit generally have the same % soluble solids but higher % titratable acidity than MG harvested fruit. Fruit in 2004 were firmer on average than fruit evaluated in Shady Lady was consistently low in firmness but had good color, whereas L-311 or L-312 fruit were consistently firmer but had poorer red color development. Results for Roma tomato varieties are shown in Table 3. Soluble solids averaged slightly less than 4.2% for 2004 Roma fruit, whereas in 2003 the average was 5.4%. The % titratable acidity was also lower in 2004 than 2003 for the Roma varieties. Red color and firmness were generally good for all varieties evaluated, although VR harvested fruit were not as firm as the ripened MG fruit. A complete report is available by mail or from the UCCE Tulare website Table 1. Ripe tomato quality measurements for 2004 variety trials. Attribute Measurement Additional Information 1. Color 2. Texture 3. Composition Objective color values using a Minolta Color meter Compression test: the force to compress the fruit a distance of 5 mm 3a. Soluble solids (SS) are measured on a refractometer 3b. Titratable acidity (TA); 10 ml juice are titrated with NaOH Data reported as Hue; this is the most useful single value to compare tomato color; see Table 2 for typical values. Hue values from usually indicate good red color. Computerized texture analyzer equipped with a 25 mm flat cylinder moving at 0.5 mm/sec. Typical range N (Table 3). 1 N =9.81 kg-force or 4.45 lb.-force. Fruit are quartered, blended. The juice is filtered and used. 5 min per fruit for sample preparation and measurements of SS and TA. Values can range from %. ph of the juice is taken as a part of these measurements. Generally there is an inverse relationship between ph and T.A. Values can range from %. 13

14 Table 2. Quality characteristics of fresh market ROUND tomatoes harvested MG and VR. MG fruit were treated with ethylene. Fruit were ripened at 20 C (68 F). Fruit were evaluated at the table-ripe stage as determined visually. F=Fresno County Trial; SJ=San Joaquin County Trial. Cultivar & Company Number of trials Red Color, Hue* Firmness, Newtons Soluble solids, % ph Titratable acidity, % MG Harvested Fruit BHN 580 (BHN) Bobcat (Syngenta) Catalyst 1 SJ L-311 (LSL Pl Sci.) 1 F L-312 (LSL Pl Sci.) 1 SJ QualiT 21 (Syngenta) QualiT 23 (Syngenta) Shady Lady (Sunseeds) SVR2935 (Seminis) Average MG VR Harvested Fruit BHN 580 (BHN) Bobcat (Syngenta) L-311(LSL Pl Sci.) 1 F Catalyst 1 SJ QualiT 21 (Syngenta) 1 F QualiT 23 (Syngenta) Shady Lady (Sunseeds) SVR2935 (Seminis) Average VR LSD Table 3. Quality characteristics of fresh market ROMA tomatoes harvested MG and VR and ripened at 20 C (68 F). Fruit were evaluated at the table-ripe stage as determined visually. See Table 1 for explanation of measurements*. Varieties are listed alphabetically. F=Fresno County Trial; SJ=San Joaquin County Trial. Cultivar & Company MG Harvested Fruit Number of trials Red Color, Hue Firmness, Newtons Soluble solids, % ph Titratable acidity, % BHN 523 (BHN) Mariana (Sakata) 1 SJ Miroma (Syngenta) Monica (Sakata) 1 SJ PX 2626 (Seminis) 1 F RFT 8109 (Syngenta) 1 SJ SD 257 (LSL Pl Sci) Average MG VR Harvested Fruit BHN 523 (BHN) Mariana (Sakata) 1 SJ Miroma (Syngenta) Monica (Sakata) 1 SJ PX 2626 (Seminis) 1 F RFT 8109 (Syngenta) 1 SJ SD 257 (LSL Pl Sci) Average VR LSD *Color and firmness data are from 3 replicates of fruits; composition data are from 3 replicates of composite samples of fruit. Data were analyzed as 2-way ANOVA for each trial. The LSD.05 value provides an estimate and is from the average LSD.05 values for the maturity stages for the 2 trials. Lower hue color values indicate redder fruits, lower firmness values indicate softer fruits. 14

15 SOURCES OF INFORMATION TOMATOES PUBLICATIONS FROM UC Many items are available at no cost from local UCCE offices or the World Wide Web. UC Vegetable Research & Information Center (UC VRIC) UC IPM (homepage) UC IPM (tomato section): PMG/selectnewpest.tomatoes.html UC Postharvest Technology: (be sure to browse the Produce Facts) UC Ag Economics: Cost of Production Guidelines or (530) UC Ag & Natural Resources Catalogue Pesticide Labels CDMS Ag Chemical Information Services Greenbook INDUSTRY ORGANIZATIONS CA Tomato Commission - Fresh Market Tomato Industry CA Tomato Research Institute A voluntary assessment by growers to support research for processing tomato crop improvement. CA Tomato Growers Association Represents growers in the bargaining, economic, public policy and business leadership arenas. CA League of Food Processors Represents and promotes processors in CA. Processed Tomato Foundation Partnership of CA tomato growers & processors to address food safety and environmental issues. Processing Tomato Advisory Board Established CA fruit quality standards and conducts grading program to assure high fruit quality. WEATHER & IRRIGATION GOVERNMENT CIMIS - CA Irrigation Management & Info System CDFA - CA Dept Water Resources - CDPR - UC IPM - Weather, day degree modeling and CIMIS CA AG Statistics Services Curly Top Virus Control Program - (559) CALIFORNIA TOMATO PROCESSORS Authentic Specialty Foods, Inc., Rosemead Campbell Soup Company, Sacramento Con-Agra Grocery Products Co. (Hunt s), Oakdale and Helm Del Monte Corporation, Hanford Escalon Premier Brands, Inc., Escalon Ingomar Packing Co., Los Banos Los Gatos Tomato Products, Huron Morning Star Packing Co., Los Banos, Riverbank, Volta, and Williams Pacific Coast Producers, Woodland Patterson Frozen Foods, Patterson Pictsweet Frozen Foods, Inc., Santa Maria Rio Bravo Tomato Co. LLC, Buttonwillow San Benito Foods, Hollister SK Foods, Inc., Lemoore and Colusa Stanislaus Food Products Co., Modesto Toma Tek, Firebaugh Unilever Bestfoods, Stockton & Merced Driers/Dehydrators Borello Farms, Inc., Morgan Hill Culinary Farms, West Sacramento Gilroy Foods, Hanford John Potter Specialty Foods, Inc., Patterson Lester Farms, Winters Mariani Nut Company, Winters Timber Crest Farms, Healdsburg Traina Dried Fruit, Patterson Valley Sundried Products, Inc., Newman 15

16 Vegetable Notes UCCE Tulare & Kings and Fresno Counties Michelle Le Strange and Shannon Mueller, Farm Advisors Newsletter Volume 1, Edition #6: Tomatoes Fresh Market & Processed in the San Joaquin Valley Vegetable Crops Production Meeting January 21, Five Points The University of California prohibits discrimination or harassment of any person on the basis of race, color, national origin, religion, sex, gender identity, pregnancy (including childbirth, and medical conditions related to pregnancy or childbirth), physical or mental disability, medical condition (cancer-related or genetic characteristics), ancestry, marital status, age, sexual orientation, citizenship, or status as a covered veteran (covered veterans are special disabled veterans, recently separated veterans, Vietnam era veterans, or any other veterans who served on active duty during a war or in a campaign or expedition for which a campaign badge has been authorized) in any of its programs or activities. University policy is intended to be consistent with the provisions of applicable State and Federal laws. Inquiries regarding the University s nondiscrimination policies may be directed to the Affirmative Action/Staff Personnel Services Director, University of California, Agriculture and Natural Resources, 300 Lakeside Drive, 6 th Floor, Oakland, CA , (510) Nonprofit Organization US Postage Paid Visalia, CA Permit No. 240